Isolated zeros destroy Fermi surface in holographic models with a lattice

TL;DR

This paper investigates how a periodic lattice potential in a holographic model affects the Fermi surface, revealing that strong lattice potentials can destroy parts of the Fermi surface and create arc-like structures due to pole-zero collisions in the Green's function.

Contribution

It demonstrates that strong lattice potentials can fragment the Fermi surface in holographic models, a novel insight into strongly correlated systems with lattice effects.

Findings

Fermi surface sectors are destroyed at strong lattice potentials.

Fermi surface becomes arc-like and disconnected.

Fermi surface poles collide with zeros of the Green's function.

Abstract

We study the fermionic spectral density in a strongly correlated quantum system described by a gravity dual. In the presence of periodically modulated chemical potential, which models the effect of the ionic lattice, we explore the shapes of the corresponding Fermi surfaces, defined by the location of peaks in the spectral density at the Fermi level. We find that at strong lattice potentials sectors of the Fermi surface are unexpectedly destroyed and the Fermi surface becomes an arc-like disconnected manifold. We explain this phenomenon in terms of a collision of the Fermi surface pole with zeros of the fermionic Green's function, which are explicitly computable in the holographic dual.